This invention relates to doors for mine stoppings, and more particularly to so-called "man doors" for use on masonry and metal mine stoppings.
So-called "stoppings" are widely used in mines to stop off flow of air in passages in the mines, a "stopping" generally being a masonry (e.g., concrete block) or metal wall installed at the entrance of a passage to block flow of air therethrough. It is often desired that such stoppings be provided with a door, which is referred to as a "man door", for occasional access to the blocked-off passage. A serious problem is encountered, however, in providing a door for a stopping because the floors of passages in mines often heave up, which may result in the door becoming unlatched and opening up for undesired flow of air therethrough, or becoming jammed, and because there may be a relative shifting of the floor, which also may result in the door becoming unlatched or becoming jammed.